1. Field of the Invention
The present invention relates to the surveying of rail track assets, such as objects or equipment in the vicinity of a railroad.
2. Description of Related Art
Assets in the vicinity of rail tracks are important for signalling and running of trains on the track. These include assets related to signalling, trackside monitoring, driver assistance and instruction, and track components.
Conventionally, in managing rail track assets, a list of well-known assets is maintained, including locations of said assets. These typically include information on important assets such as signals, but may not include information on smaller or less significant assets. The list of assets is generally maintained manually, at high cost. This is highly time consuming, and the list quickly becomes out of date.
Previously, track surveys were carried out by a team of inspectors who would walk along the track or travel on slow speed motorised platforms, making records of track components and their condition and location. This process of data capture was very slow, as the speed to travel needed to be sufficiently slow in order that the track inspectors could record data. Any interruption to normal use of the track for higher speed passenger and freight vehicles is detrimental. If inspectors travel on conventional passenger trains, then it is necessary to conduct multiple passes of the same stretches of the track to accurately identify all rail track assets of potential concern.
More recently, digital cameras have been used on board an inspection vehicle, to record video of the track and its surroundings, and to log location data. Typically, image data is transferred to an off-site computer, where a human operator, with the assistance of desktop software, reviews the collected data and manually selects assets of interest from the images. This is typically a slow and expensive process; it may take several weeks or months to complete a survey of a moderately sized track segment, in which time the conditions of the assets may have changed significantly.
There have been more recent attempts to use video image frame processing techniques to identify assets against predetermined templates for a small number of asset types. Whilst such techniques can potentially identify and classify different types of asset, this does not result in a complete surveying system in itself because the operational risk posed by the identified assets is not inferred by the asset type alone. Manual inspection/assessment would rely on the inspector to drawn upon a significant level of underlying knowledge about the different types of assets and the risks that could be posed to railway track and/or rail vehicles thereby. Thus, even though the process of capturing image data for a survey has been simplified and made accessible to an inspector, the risk assessment itself remains a substantially manual process and the time taken to complete a survey thus increases generally linearly as a function of the length of track to be inspected.
One particular complexity of an asset inspection system for use in rail applications is that video image processing can be computationally intensive. The requirement for data to be amassed and communicated to a central location for processing, coupled with the detailed processing of the recorded data, can lead to a significant delay between the inspection itself and the deduction of any action required based on the inspection. Furthermore it can be problematic handling the large volumes of image/video data generated.
It is an object of the present invention to provide a track asset surveying system that overcomes or substantially mitigates one or more of the above disadvantages associated with conventional track asset surveying. It may be considered an additional or alternative aim of the invention to provide a system that can provide useful inspection results closer to in real time.
Although great strides have been made, considerable shortcomings remain.